HomeLAN Fed is reporting that the latest issue of PC Gamer has a story on the first expansion pack for Call of Duty, titled United Offensive. In development at Return to Castle Wolfenstein developer Gray Matter Studios, United Offensive will feature three separate single player campaign just like the original game. The expansion pack is due out this fall. In related news Activision sends along word that GameSpy is hosting a developer chat with Infinity Ward today at 6PM CST.